1、Designation: D6121 15Standard Test Method forEvaluation of Load-Carrying Capacity of Lubricants UnderConditions of Low Speed and High Torque Used for FinalHypoid Drive Axles1This standard is issued under the fixed designation D6121; the number immediately following the designation indicates the year
2、 oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis test method is written for use by laboratories that
3、 use the portions of the test method that refertoASTM Test Monitoring Center (TMC) services (see AnnexA1). Laboratories that choose not to usethe TMC services may simply disregard these portions.The TMC provides reference oils, and engineering and statistical services to laboratories that desireto p
4、roduce test results that are statistically similar to those produced by laboratories previouslycalibrated by the TMC.In general, the Test Purchaser decides if a calibrated test stand is to be used. Organizations such astheAmerican Chemistry Council require that a laboratory utilize the TMC services
5、as part of their testregistration process. In addition, the American Petroleum Institute and the Gear Lubricant ReviewCommittee of the Lubricant Review Institute (SAE International) require that a laboratory use theTMC services in seeking qualification of oils against their specifications.NOTE 1The
6、advantage of using the TMC services to calibrate test stands is that the test laboratory (and hence theTest Purchaser) has an assurance that the test stand was operating at the proper level of test severity. It should also beborne in mind that results obtained in a non calibrated test stand may not
7、be the same as those obtained in a test standparticipating in the ASTM TMC services process.1. Scope*1.1 This test method is commonly referred to as the L-37test.2This test method covers a test procedure for evaluatingthe load-carrying, wear, and extreme pressure properties of agear lubricant in a h
8、ypoid axle under conditions of low-speed,high-torque operation.1.2 This test method also provides for the running of the lowaxle temperature (Canadian) L-37 test. The procedure for thelow axle temperature (Canadian) L-37 test is identical to thestandard L-37 test with the exceptions of the items spe
9、cificallylisted in Annex A9. The procedure modifications listed inAnnex A9 refer to the corresponding section of the standardL-37 test method.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are prov
10、ided for information onlyand are not considered standard.1.3.1 ExceptionsIn Table A12.1, the values stated in SIunits are to be regarded as standard. Also, no SI unit isprovided where there is not a direct SI equivalent.1.4 This standard does not purport to address all of thesafety concerns, if any,
11、 associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific warninginformation is given in Sections 4 and 7.1This test method is under the jurisd
12、iction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.B0.03 on Automotive Gear Lubricants sheared-off particles either re-main affixed to the harder of the mating surfaces or act as wearparticles between the surfaces.ASTM
13、Distress Rating Manual No. 213.1.3 broken gear tooth, na gear tooth where a portion ofthe tooth face is missing and the missing material includessome part of the top land, toe, heel, or coast side of the tooth.3.1.3.1 DiscussionThis condition is distinct from andmore extensive than “chipping,” which
14、 is defined in 3.1.5.3.1.4 burnish, non ring and pinion gears, an alteration ofthe original manufactured surface to a dull or brightly polishedcondition. ASTM Distress Rating Manual No. 213.1.5 chipping, non ring and pinion gears, a conditioncaused in the manufacturing process in which a small irreg
15、ularcavity is present only at the face/crown edge interface. Theedge-chipping phenomenon occurs when sufficient fatiguecycles accumulate after tooth surface wear relieves the com-pressive residual stress on the tooth profile side of theprofile-to-topland interface. Chipping within 1 mm of theface/cr
16、own edge interface is to be called chipping, notpitting/spalling. ASTM Distress Rating Manual No. 213.1.6 corrosion, nin final drive axles, a general alterationof the finished surfaces of bearings or gears by discoloration,accompanied by roughening not attributable to mechanicalaction. ASTM Distress
17、 Rating Manual No. 213.1.7 deposits, nin final drive axles, material of pasty,gummy, or brittle nature adhering to or collecting around anyof the working parts.ASTM Distress Rating Manual No. 213.1.8 discoloration, non ring and pinion gears, any al-teration in the normal color of finished steel surf
18、aces.ASTM Distress Rating Manual No. 213.1.9 pitting, non ring and pinion gears, small irregularcavities in the tooth surface, resulting from the breaking out ofsmall areas of surface metal.ASTM Distress Rating Manual No. 213.1.10 ridging, non ring and pinion gears, an alteration ofthe tooth surface
19、 to give a series of parallel raised and polishedridges running diagonally in the direction of sliding motion,either partially or completely across the tooth surfaces of gears.ASTM Distress Rating Manual No. 213.1.11 rippling, non ring and pinion gears, an alterationof the tooth surface to give an a
20、ppearance of a more or lessregular pattern resembling ripples on water or fish scales.ASTM Distress Rating Manual No. 213.1.12 scoring, non ring and pinion gears, the rapidremoval of metal from the tooth surfaces caused by the tearingout of small contacting particles that have welded together asa re
21、sult of metal-to-metal contact. The scored surface ischaracterized by a matte or dull finish.ASTM Distress Rating Manual No. 213.1.13 scratching, non ring and pinion gears, an altera-tion of the tooth surface in the form of irregular scratches, ofrandom length, across the tooth surface in the direct
22、ion ofsliding of the surfaces.ASTM Distress Rating Manual No. 213.1.14 spalling, non ring and pinion gears, the breakingout of flakes of irregular area of the tooth surface, a conditionmore extensive than pitting.ASTM Distress Rating Manual No. 213.1.15 surface fatigue, non ring and pinion gears, th
23、efailure of the ring gear and pinion material as a result ofrepeated surface or subsurface stresses that are beyond theendurance limit of the material. It is characterized by theremoval of metal and the formation of cavities.AGMA National Standard3.1.16 wear, non ring and pinion gears, the removal o
24、fmetal, without evidence of surface fatigue or adhesive wear,resulting in partial or complete elimination of tool or grindingmarks or development of a discernible shoulder ridge at thebottom of the contact area near the root or at the toe or heel endof pinion tooth contact area (abrasive wear).ASTM
25、Distress Rating Manual No. 213For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from Standardization
26、Documents Order Desk, Bldg 4, Section D, 700Robbins Avenue, Philadelphia, PA 191115098.5American Gear Manufacturers Assn. (AGMA), 1500 King St., Suite 201,Alexandria, VA 22314.6Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001.7Formerly known as CRC
27、 Manual 21. Available from the ASTM website,www.astm.org, (TMCMNL21).D6121 1524. Summary of Test Method4.1 Prior to each test run, inspect the test unit (final axleassembly) and measure and record confirming manufacturingspecifications.4.2 Begin the test when the axle assembly is installed on thetes
28、t stand and charged with test lubricant.4.3 Gear Conditioning PhaseRun the charged test unit for100 min at 440 wheel r/min and 395 lbf-ft (535 Nm) torqueper wheel, maintaining an axle sump temperature of 297F(147 C). (WarningHigh-speed rotating equipment, electri-cal shock, high-temperature surfaces
29、.)4.4 Gear Test PhaseNext, run the test unit for 24 h at theoperating conditions dictated by the hardware batch and typecombination (see 10.2.3.1).4.5 The test is completed at the end of the gear test phase.Visually inspect the test parts.4.5.1 Remove the ring gear, pinion, and pinion bearing, andra
30、te for various forms of distress. Use the condition of the ringgear and pinion to evaluate the performance of the test oil.5. Significance and Use5.1 This test method measures a lubricants ability to protectfinal drive axles from abrasive wear, adhesive wear, plasticdeformation, and surface fatigue
31、when subjected to low-speed,high-torque conditions. Lack of protection can lead to prema-ture gear or bearing failure, or both.5.2 This test method is used, or referred to, in the followingdocuments:5.2.1 American Petroleum Institute (API) Publication1560.85.2.2 STP-512A.95.2.3 SAE J308.5.2.4 Milita
32、ry Specification MIL-PRF-2105E.5.2.5 SAE J2360.6. Apparatus6.1 Test UnitThe test unit is a new complete hypoid truckaxle assembly less axle shafts, Dana Model 60, 5.86 to 1ratio.10See Annex A9 for part numbers.6.2 Test Stand and Laboratory Equipment:6.2.1 Axle VentVent the axle to the atmosphere thr
33、oughoutthe entire test and arrange the vent so that no water enters thehousing.6.2.2 Axle CoverThe axle cover may have a port installedto allow for ring gear inspection after the gear condition phase(see 10.1). See Fig. A5.1 for an example.6.2.3 Test Stand ConfigurationMount the complete as-sembly i
34、n a rigid fixture as shown in Fig. A6.1. Mount the testunit in the test stand with pinion and axle shaft centerlineshorizontal.6.2.4 Temperature ControlThe test axle housing shallinclude a means of maintaining the lubricant at a specifiedtemperature. This shall include a thermocouple, a temperaturer
35、ecording system, and a cooling method.6.2.4.1 ThermocoupleDetermine the thermocouple loca-tion on the rear cover using the cover plate temperature sensorlocating device as shown in Fig. A7.1.(1) Install the thermocouple such that the thermocoupletip is flush with the cover plate lip by placing the c
36、over plateface on a flat surface and inserting the thermocouple into thecover plate until the thermocouple tip is flush with the flatsurface.(2) Lock the thermocouple into place.6.2.4.2 Temperature Recording SystemThe temperaturerecording system shall record the temperature of the test oilthroughout
37、 the test.6.2.4.3 Axle CoolingUse three spray nozzles to distributewater over the cover plate and axle housing as shown in Fig.A8.1. Actuate the water control valve by the temperature PIDcontrol system. See A9.3.2.1 for L-37 Canadian Version test.(1) Spray nozzles11shall be any combination of the fo
38、l-lowing part numbers depending on how the system is plumbed:Straight Male NPT (Part No. 3/8GG-SS22), 90 Male NPT(Part No. 3/8GGA-SS22), Straight Female NPT (Part No.3/8G-SS22), and 90 Female NPT (Part No. 3/8GA-SS22).(2) Use a single control valve to control the cooling watersupply. The control sha
39、ll be a12 in. (12.7 mm) two-way, Clinear trim, air to close, Research Control valve. Use a singlePID loop to maintain the axle lubricant temperature control forboth the Standard and Canadian version test. A separate PIDloop control for each version is not permitted. See A9.3.2.2 forL-37 Canadian Ver
40、sion test.(3) Use only38 or12 in. (9.5 mm or 12.7 mm) line materialto the spray nozzles.(4) Use a minimum supply water pressure of 25 psi (172kPa) to the control valve.(5) Use an axle box cover as shown in Fig. A8.2. Thepurpose is to contain water and eliminate drafts.(6) Use a locating pin or stop
41、block as an indexing deviceto ensure that all subsequent axle installations are consistentlyinstalled perpendicular with the axle housing cover to engineand transmission driveshaft centerline.6.2.5 Power SourceThe power source consists of agasoline-powered V-8 engine capable of maintaining testcondi
42、tions.6.2.6 Dynamometers and Torque Control SystemUse twoaxle dynamometers with sufficient torque absorbing capacity tomaintain axle torque and speed conditions. Suitable control8“Lubricant Service Designations for Automotive Manual Transmissions,Manual Transaxles, and Axles,” available from America
43、n Petroleum Institute, 1220L St. NW, Washington, DC 20005.9“Laboratory Performance Tests for Automotive Gear Lubricants Intended forAPI GL-5 Service.”10The sole source of supply of the apparatus known to the committee at this timeis Dana Corp., P.O. Box 2424, Fort Wayne, IN 46801. If you are aware o
44、f alternativesuppliers, please provide this information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.11The sole source of supply of the apparatus known to the committee at this timeis Spra
45、y Systems Company, and the spray nozzles can be purchased through E.I.Pfaff Company, 3443 Edwards Road, Suite D, Cincinnati, OH 45208. If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a
46、meetingof the responsible technical committee,1which you may attend.D6121 153equipment with sensitivity of adjustment to permit mainte-nance of test conditions is required.6.2.7 Dynamometer Connecting ShaftsFabricate shaftsconnecting the dynamometer to the axle shafts. Shafts shall bestrong enough t
47、o handle the torques encountered and shall bedynamically (spin) balanced.6.2.8 Drive Shaft and Universal JointsFabricate a shaftwith universal joints connecting the manual transmission andtest axle. The shaft shall have a 4 6 0.2-in. (10.1 cm 60.51 cm) outside diameter with a 0.095 6 0.005 in. (0.24
48、 cm 60.013 cm) wall thickness. Shaft and universal joints should bestrong enough to handle the torques encountered and shall bedynamically (spin) balanced.6.2.9 Transmission and CouplingCouple the engine to thetest unit through a clutch and manual transmission of sufficienttorque carrying capacity t
49、o operate normally under test condi-tions.6.3 Speed Measuring and Control System, capable of mea-suring speed of both axles and also of maintaining testconditions.7. Reagents and Materials7.1 Sealing Compound, where necessary, Permatex No. 2,or equivalent.7.2 SolventUse only mineral spirits meeting the require-ments of Specification D235, Type II, Class C for AromaticContent (0-2% vol), Flash Point (142F/61C, min) and Color(not darker than +25 on Saybolt Scale or 25 on Pt-Co Scale).(WarningCombustible. Health hazard.) Obtain a Certificate
